Metschnikowia pulcherrima has recently attracted attention as a promising biotechnological tool for its agri-food applications. It shows effectiveness as biocontrol agents in areas such as winemaking, cheese fermentation, and the control of key postharvest and soil-borne fungal pathogens in agriculture. It belongs to the so-called ‘pulcherrima clade’, together with 10 other species. All of them produce the iron-chelate pigment pulcherrimin and have antagonistic effects on many microorganisms. In this study, 68 presumptive Metschnikowia spp. isolates from grapes and fruits were subjected to metabolic and genotypic characterization. Species identification was performed by sequencing the D1/D2 domain of the 26S rRNA gene. Strain differentiation was carried out using M13-RAPD-PCR analysis. The strains were evaluated for copper resistance and cell surface hydrophobicity. Moreover, novel primer pairs were developed to amplify 3 orthologous genes possibly involved in copper metabolism. The genes encoded for two transporters of copper and a copper chaperone. The primers were designed by analysing the genome of the APC 1.2 strain. All strains were identified as M. pulcherrima. M13-based molecular typing grouped the isolates into nine clusters, some of which consisted of a single strain. Twelve strains tolerated concentrations of up to 0.2 g/L of copper, and the copper resistance was higher in strains isolated from organic grapes and musts than in those from fruits, suggesting a domestication process in these species. Surface hydrophobicity was strain-dependent, with copper-resistant strains generally exhibiting higher hydrophobicity than the others. All genes were up-regulated in the presence of copper. The highest expression was detected in the strains able to grow in the presence of 0.2 g/L of copper, suggesting their possible involvement in copper tolerance and metabolism. Further studies are necessary to better understand the specific aspects of copper metabolism and trafficking in M. pulcherrima.
Exploring copper resistance diversity in Metschnikowia pulcherrima strains
Perpetuini G.;Rossetti A. P.;Adesuyi O. P.;Tofalo R.
2025-01-01
Abstract
Metschnikowia pulcherrima has recently attracted attention as a promising biotechnological tool for its agri-food applications. It shows effectiveness as biocontrol agents in areas such as winemaking, cheese fermentation, and the control of key postharvest and soil-borne fungal pathogens in agriculture. It belongs to the so-called ‘pulcherrima clade’, together with 10 other species. All of them produce the iron-chelate pigment pulcherrimin and have antagonistic effects on many microorganisms. In this study, 68 presumptive Metschnikowia spp. isolates from grapes and fruits were subjected to metabolic and genotypic characterization. Species identification was performed by sequencing the D1/D2 domain of the 26S rRNA gene. Strain differentiation was carried out using M13-RAPD-PCR analysis. The strains were evaluated for copper resistance and cell surface hydrophobicity. Moreover, novel primer pairs were developed to amplify 3 orthologous genes possibly involved in copper metabolism. The genes encoded for two transporters of copper and a copper chaperone. The primers were designed by analysing the genome of the APC 1.2 strain. All strains were identified as M. pulcherrima. M13-based molecular typing grouped the isolates into nine clusters, some of which consisted of a single strain. Twelve strains tolerated concentrations of up to 0.2 g/L of copper, and the copper resistance was higher in strains isolated from organic grapes and musts than in those from fruits, suggesting a domestication process in these species. Surface hydrophobicity was strain-dependent, with copper-resistant strains generally exhibiting higher hydrophobicity than the others. All genes were up-regulated in the presence of copper. The highest expression was detected in the strains able to grow in the presence of 0.2 g/L of copper, suggesting their possible involvement in copper tolerance and metabolism. Further studies are necessary to better understand the specific aspects of copper metabolism and trafficking in M. pulcherrima.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
